Method of concentrating distillery still slop



E. Q. PATTEE .Fam ZG, 1948.

METHOD OF CONCENTHATING DISTILLERY STILL SLOP Filed 0G12. l5, 1945 INVENTOR.

Patented Jan. 20, 1948 OFFICE METHOD F CONCENTRATING DISERY STILL SLOP Ellis C. Pattee,

National Distillers Pr poration of Virginia Cincinnati, Ohio, assigner to oducts Corporation, a cor- Application October 15, 1943, Serial No. 506,317

(Cl. 15in-47) 4 Claims. l

This invention is a new and useful process for concentrating distillery slop. The invention will be understood from the following description read in conjunction with the drawing, the single figure of which is a diagrammatic showing in side elevation with parts in section of apparatus in which the invention may be carried out.

In the manufacture of distilled liquors and of alcohol by the fermentation of cereals, the cereal is first mashed and then fermented and then distilled. The residue remaining in the still is known as distillery slop and contains soluble materials in solution and insoluble materials in suspension.

In accordance with my invention the distillery slop from any suitable source is introduced through pipe I to screen 2. The screen surface 3 of screen 2 may range from 20 to 100 mesh (Tyler specifications) and is preferably of about 60 mesh. Preferably the screen is of the oscillating or shaking type embodying means for moving the material retained on top oi' the screen progressively forward so that this material is discharged continuously from the lower end 4 of the screen surface and diverted from the system by means of chute 5. The material passing through the screen includes all the soluble solids and includes also the liner or smaller insoluble solids. This material ows downwardly within the trough 8 into pipe 1. The larger insoluble solids in chute 5 may, if desired, be pressed and combined with the liquid in pipe 1. The liquidV in pipe 1 is moved continuouslyby means of pump 8 through pipe 9 into the pipe still il. The pipe still il includes the continuous tubular heater l2 mounted in the refractory setting I3 and heated by any suitable means, such as burner I4. Sullicient heat is introduced into the liquid in its passage through heater i2 to raise it to the boiling point and in addition to vaporize a part of the water content therein. The amount of water so vaporized may range from to 40% of the entire Water content and preferably is about 25% of the entire water content when three subsequent evaporative effects are employed. If desired, some pressure in excess of atmospheric may be maintained on the material in heater i2 by means of the pressure reduction valve l5. The material so heated is then discharged through pipe I8 into the drum il in which separation between the liquor and vapor takes place. The liquid portion accumulates in the cone bottom i8 of drum I l passing ofi. continuously through pipe i9 controlled by valve into the iirst unit 2l of a battery of evaporators. The steam is conducted away from the drum l'l through pipe tt, conthe expressed liquor trolled by valve 23, and so introduced into the unit 2 l, in which it passes in indirect heat exchanging relationship to the liquid introduced through pipe I9. All or part of the steam is condensed ln unit 2l, the condensate being withdrawn through the pipe 2l. Evaporation of the material introduced through pipe I8 takes place in the unit 2i. the steam so produced passing oil through pipe 25 into the next succeeding evaporator unit 28. The partly concentrated distillery slop passes out of unit 2l through pipe 2l into the unit 26. In this unit the steam from pipe 25 is passed in indirect heat exchanging relationship to the partly concentrated distillery slop so introduced, with the result that all or part of the steam is condensed in this unit, the condensate passing of! through the pipe it. Further evaporation of the water content of the distillery slop occurs in unit 26, the steam so produced passing of! through pipe 29 into the next succeeding unit 3i. The more nearly concentrated distillery slop passes out of unit 2B through pipe 32 into unit 2i. In this unit the steam from pipe t9 passes in indirect heat exchanging relationship to the distillery slop so introduced, with the result that all or part of the steam is condensed, the condensate passing out of the unit through pipe 33. In consequence` of this evaporation of the water content of the dis tillery slop so introduced occurs, the steam so produced passing ou through pipe 34 into the barometric condenser l5 by which it is condensed and removed.

It will, of course, be understood that the lowest absolute pressure is maintained on the slop in unit 3|. that a slightly higher absolute pressure is maintained on the slop in unit 26, that a still higher absolute pressure is maintained on the slop in unit 2i, and ythat a still higher absolute pressure is maintained on the slop in the drum l l, to the end that the necessary temperature difierential for eiiicient evaporation may exist in each auch receptacle.

The concentrated distillery slop passes out of unit 3i through pipe 38 into pump 3l. At this stage the moisture content will range between 20 and 40% of the whole, and is preferably ap proximately 30%. This material is pumped continuously throughpipe il' into the distributor 38.

The products of combustion produced by burner it after passing in indirect heat exchanging relationship through the material passing through heater i2 move out ci' refractory setting il through the stack El by which they are discharged into the lower part of the spray drying tower 42. These products of combustion move upwardly within the tower 4,2, passing therein in direct heat exchanging relationship to the concentrated distillery slop introduced into the upper part of the tower in finely divided form by the distributor 38. After so passing the products of combustion move out of the system through the stack 43.

In moving downwardly within the tower 42, the distillery s1op is converted into nely divided solid form, in which the moisture content may range between 2 and 12% of the whole and is preferably approximately 8%. This material is continuously collected and withdrawn by means of the sloping bottom 44 and the chute 45.

The product so obtained is firm and chemically stable. It is high in proteins, especially the water soluble'proteins, and in vitamin content and is a valuable feed stock.

The foregoing description is for purposes of illustration and not of limitation and itis therefore my intention that the invention be limited only by the following claims or their equivalent wherein I have endeavored to claim broadly all inherent novelty.

I claim:

1. Method of concentrating distillery still slop which comprises screening the same thereby removing coarse suspended solids therefrom and thereafter forcing such slop as a continuous stream through a tubular Zone in which it is indirectly heated to a temperature above 100 C., and vaporizing not in excess of 1040% of the water content of said slop in said zone at a temperature in excess of 100 C., discharging the stream so heated into a separating zone and conductng the steam so withdrawn into indirect heat exchanging relationship to the concentrated s1op so withdrawn while maintaining a pressure on said slop below that obtaining in said separating zone.

2. Method of concentrating distillery still slop which comprises screening the same thereby renoving coarse suspended solids therefrom and thereafter forcing such slop as a continuous stream through a tubular zone in which it is indirectly heated to a temperature above 100 C. by passing it in said tubular zone in indirect heat exchanging relationship with gaseous products of combustion, and vaporizing not in excess of 10- 40% of the water content of said slop in said syrup into direct contact with the said gaseous products of combustion thereby producing dried concentrated slop.

3. Method of concentrating distillery still slop which comprises screening the same thereby removing coarse suspended solids therefrom and thereafter forcing such slop as a continuous stream through a tubular zone in which it is indirectly heated to a temperature above 100 C. by passing it in said tubular zone in indirect heat exchanging relationship with gaseous products of combustion, and vaporizing not in excess of 10-40% of the water content of said s1op in said zone at a temperature in excess of 100 C. thereafter conducting away the said gaseous products of combustion, discharging the stream so heated into a separating zone, continuously removing steam and concentrated slop as independent streams from said separating zone, conducting the steam so Withdrawn into indirect e heat exchanging relationship to the concentrated slop so withdrawn while maintaining a pressure on said slop below that obtaining in said separating zone thereby producing a syrup, subdividing the said syrup and passing the subdivided syrup in direct contact with the said gaseous products of combustion thereby producing dried concen- -trated distillery s1op.

4. In the concentrating of distillery still slop the improvement which comprises screening said slop, thereby removing coarse suspended solids therefrom, thereafter forcing such slop as a continuous stream through a tubular zone, indirectly heating said slop contained in said tubular zone with gaseous products ci combustion and lvaporizing not in excess of substantially l040% of the water content of said slop in said zone at a temperature in excess of 100 C., in order to avoid decomposition of the slop discharging the partly vaporized stream of slop so heated into a separating zone, continuously removing concentrated slop as an independent stream from said separating zone, and continuously removing steam as an independent stream from said separating zone to thereby create a readily available source of indirect heat.

zone at a temperature in excess of 100 C. thereafter conducting away the said gaseous products of combustion, discharging the stream so heated into a separating zone, continuously removing steam and concentrated slops as independent streams from said separating zone, conducting the steam so withdrawn into indirect heat exchanging relationship to the concentrated slop so withdrawn while maintaining a pressure on said s1op below that obtaining in said separating zone thereby producing a syrup and conducting said ELLIS C. PATTEE.

REFERENCES ClTED The following references are of record in the `file of this patent:

UNITED STATES PATENTS Number Name Date 2,225,428 Christensen Dec. 17, 1940 2,037,006 Clayton Apr. 14, 1936 1,016,160 Kestner Jan. 30, 1912 2,193,786 Thurman Mar. 12, 1940 2,263,608 Brown Nov. 25, 1941 1,033,558 Dunn July 23, 1912 

